The present invention relates to a multi-joint arm control system for effectively guiding a multi-joint arm robot apparatus toward a target in a narrow space to which an operator cannot gain access.
Facilities such as tower tank, nuclear reactor, fusion reactor and shielding cell in a nuclear fuel reprocessing plant have neither entrance nor space large enough to allow technical personnel to enter or work in and contain harmful radioactive rays and the like. Therefore, it is usually impossible for personnel to enter directly inside these facilities to check them or work in them. With these facilities, it is necessary that the working person be located at a safe site and remotely operate an industrial robot arranged in these facilities or be allowed into them through a small entrance to check or work in them.
It is preferable that such a robot is of a multi-joint arm type wherein a plurality of unit arms are coupled through joints in order to facilitate the avoidance of contact with various obstacles.
A multi-joint arm which is simple in construction and easy in control is disclosed in U.S. patent application Ser. No. 418,208, filed on Sept. 15, 1982, now U.S. Pat. NO. 4,480,495. In this multi-joint arm, the angle formed by two adjacent arms connected by a joint is controlled by a motor, so that a relatively complex posture can be achieved. For this reason, this multi-joint arm has a suitable construction for avoiding obstacles, while being guided toward a target.